A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.
A computer program listing for the present invention is set forth in a Microfiche Appendix which is on file in the present patent application. This Microfiche Appendix includes two (2) sheets, with the first sheet having sixty (60) frames and the second sheet having thirty-nine (39) frames.
1. Field of the Invention
The present invention relates to voltage monitoring devices. More specifically, the invention relates to small, portable, AC voltage measuring devices which can readily be used to monitor and record abnormal voltage conditions in supply electricity. The invention also relates to the use of several of these monitoring devices over a wide geographical area, through a communications network such as a local area network (LAN) or wide area network (WAN).
2. Related Art
Various devices for measuring voltage abnormalities are known in the art. Such devices are designed to determine when dangerous or otherwise undesirable voltage conditions exist on AC power lines.
For example, voltage spikes, as well as more enduring overvoltage and undervoltage conditions, are known to cause damage or improper functioning of equipment, especially computers. By monitoring the occurrence of voltage abnormalities, preventive or corrective action may be taken to prevent further occurrences. Moreover, when a voltage abnormality is disproved at a time of equipment malfunction, troubleshooting may focus on the equipment itself and not on the power supply to the equipment.
Unfortunately, most known systems have been crude in operation or limited in their applications. Some monitoring systems merely signal an abnormality locally, so that an individual user would have to be physically present during an alarm condition, or inspect the alarm unit soon after an alarm condition. Also, known systems have been deficient in their ability to comprehensively specify the time, duration, and nature of any electrical supply abnormalities. Further, many known systems have been physically large, making them unsuitable for distribution to or movement among various sites. These limitations have made it difficult to localize the cause of equipment damage or malfunction, confirm the time it occurred, or determine the reason that it occurred.
Moreover, in many institutions such as universities, in which a substantially large number of electrically sensitive instruments such as computer terminals are broadly distributed, a comprehensive monitoring system is needed to efficiently determine the cause of otherwise perplexing problems.
Therefore, there is a need in the art to provide a simple, portable, but functionally sophisticated and comprehensive, electrical power measuring, storing and reporting device. Moreover, there is a need in the art to provide such a monitoring device which can be remotely controlled and accessed through a communications network. It is to meet this need that the present invention is directed.
The present invention provides a portable monitoring unit, preferably adapted for plugging into a common wall outlet, having circuitry for monitoring the voltage provided through the outlet. In addition to the monitoring circuitry, the invention preferably includes a microprocessor for analyzing the monitored waveform. The microprocessor recognizes specific voltage occurrences, based upon parameters which can be varied by the user.
The invention also has a storage memory for storing samples of the input waveform. The invention employs this memory to keep a log of particular waveform information, over predetermined periods of time. In this fashion, the memory stores waveform information in an arrangement that can be easily downloaded to a computer, local area network, or other destination, for conversion into useful histograms, charts, and the like.
In addition, the invention also has a communication interface, so that it can provide the information it collects to a remote location through a communications network, such as a LAN or a WAN. Further, the operation of the invention can be controlled from a remote location through such a communications network by way of the communication interface.
Preferably, the invention also is provided with a local visual display and an alarm indicator.